Al-Sha'bi narrates that Sayyiduna Jabir bin Samurah (may Allah be pleased with him) said: I was with my father in the presence of the Prophet (peace and blessings be upon him), and he (peace and blessings be upon him) said: "This Ummah will have twelve custodians; whoever abandons them will not harm them." Then the Messenger of Allah (peace and blessings be upon him) said something quietly that I could not hear, so I asked my father: What did the Prophet (peace and blessings be upon him) say quietly? He said: "All of them will be from Quraysh."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 1781